Long lines

ABSTRACT

Longline comprises at least one polyamide monofil A) with at least one cylindrical hollow body (stopper) B) secured on the polyamide monofil surface, wherein said stopper B) consists essentially of a thermoplastic elastomer having a Shore D hardness (as defined in DIN 53505) of at least 50.

BACKGROUND OF THE INVENTION

The present invention relates to longlines comprising at least onepolyamide monofil A) with at least one cylindrical hollow body (stopper)B) secured on the polyamide monofil surface, wherein said stopper B)consists essentially of a thermoplastic elastomer having a Shore Dhardness (as defined in DIN 53 505) of at least 50.

The present invention further relates to processes for manufacturinglonglines according to the present invention and to their use formanufacturing nets, angling lines, fishlines and continuous lines forcatching fish and to the resulting continuous lines, angling lines andfishlines.

Longlines comprising stoppers and monofils of plastic are known fromCH-A 641 637 and EP-A 445 810.

The monofils comprise polyamide and the stopper comprises athermoplastic polymer which is either welded onto the monofilament in atwo-part form or is provided with spikes and bonded to the monofilamentby fusion or by spraying on by means of injection-molding processes. Theadhesion can be brought about mechanically by fusion and/or chemically(adhesion forces between various components).

The stoppers generally serve to limit the mobility of rotors or clips towhich hooklines and hooks are attached.

The stoppers applied by existing processes exhibit too little adhesion,even if the same polymer material is used for stopper and line.

Commercially available systems tried to improve the adhesion by means ofglassfiber-including stoppers.

Especially commercial fishing, since the use of driftnets isincreasingly prohibited, requires systems providing a slippageresistance (pulloff resistance of the stopper) of almost 1000 N (in themoist state!). Such continuous lines are kilometers in length andrequire a very high tensile strength. Given a length of from 10 to 20 kmowing to the weight of hooked fish or hangers on the bottom, highslippage resistances of the stoppers and a high line breaking strengthare desirable.

Furthermore, commercially available systems exhibit an unsatisfactoryknot strength of the monofil, since knotting a monofilament considerablyreduces the tensile strength in the region of the knot.

SUMMARY OF THE INVENTION

It is an object of the present invention to provide longlines whosestoppers have a higher slippage resistance in the moist state and whosemonofil lines exhibit improved knot strength.

We have found that this object is achieved by the longlines defined atthe beginning. Preferred embodiments are revealed in the subclaims.

We have also found processes for producing these longlines and alsotheir use for manufacturing continuous lines, angling lines andfishlines.

BRIEF DESCRIPTION OF THE DRAWING

The drawing is an illustrative diagram of a section of a continuous linefor catching fish made in accordance with this invention.

Polyamide monofilament A) of the longlines of this invention customarilycomprises one or more polyamides which may include up to 30% by weight,preferably up to 15% by weight (based on 100% by weight of polyamide),of further, additive substances and processing aids.

The monofils are generally from 1 to 5, in particular from 1.5 to 2.5,mm in diameter.

Suitable polyamides for the monofils have a viscosity number (VN) of atleast 180 ml/g, preferably at least 200 ml/g, especially at least 220ml/g; determined in a 0.5% strength by weight solution in 96% strengthby weight sulfuric acid at 25° C. in accordance with ISO 307.

Semicrystalline or amorphous resins having a molecular weight (weightaverage) of at least 5000 as described for example in U.S. Pat. Nos.2,071,250, 2,071,251, 2,130,523, 2,130,948, 2,241,322, 2,312,966,2,512,606 and 3,393,210 are preferred.

Examples thereof are polyamides derived from lactams having from 7 to 13ring members, such as polycaprolactam, polycapryllactam andpolylaurolactam, and also polyamides obtained by reacting dicarboxylicacids with diamines.

Suitable dicarboxylic acids include alkanedicarboxylic acids having from6 to 12, in particular from 6 to 10, carbon atoms and aromaticdicarboxylic acids. Exemplary acids are adipic acid, azelaic acid,sebacic acid, dodecanedioic acid and terephthalic and/or isophthalicacid.

Suitable diamines include in particular alkanediamines having from 6 to12, in particular from 6 to 8, carbon atoms and also m-xylylenediamine,di(4-aminophenyl)methane, di(4-aminocyclohexyl)methane,2,2-di(4-aminophenyl)propane or 2,2-di(4-aminocyclohexyl)propane.

Preferred polyamides are polyhexamethyleneadipamide,polyhexamethylen-esebacamide and polycaprolactam.

Also suitable are polyamides obtainable for example by condensation of1,4-diaminobutane with adipic acid at elevated temperature (nylon-4,6).Processes producing polyamides of this structure are described forexample in EP-A 38 094, EP-A 38 582 and EP-A 39 524.

Also suitable are polyamides obtainable by copolymerization of two ormore of the aforementioned monomers or mixtures of a plurality ofpolyamides in any mixing ratio.

Particularly preferred polyamides are copolyamides 6/66, especiallythose having an 80:20, preferably 85:15, ratio of 6/66 units (eg.Ultramid® C from BASF AG).

The polyamides may include further, additive substances and processingaids.

Customary additives include for example stabilizers and oxidationinhibitors, agents against thermal decomposition and decomposition dueto ultraviolet light, lubricants, demolding agents, dyes, pigments andplasticizers and also toughening polymers (rubbers).

Oxidation inhibitors and thermal stabilizers which can be included inthe thermoplastic compositions of this invention include for examplehalides selected from the group of metals of group I of the PeriodicTable, eg. lithium, sodium, potassium halides, and copper(I) halides,eg. chlorides, bromides or iodides, or mixtures thereof It is alsopossible to use sterically hindered phenols, secondary, aromatic amines,hydroquinones, substituted representatives of this group and mixturesthereof, preferably in concentrations of up to 1% by weight, based onthe weight of the mixture.

Examples of UV stabilizers include substituted resorcinols, stericallyhindered phenols, salicylates, benzotriazoles and benzophenones, whichcan generally be used in amounts of up to 2% by weight.

Lubricants and demolding agents, which can generally be added to thepolyamide in an amount of up to 1% by weight, include for examplelong-chain fatty acids or derivatives thereof such as stearic acid,stearyl alcohol, alkyl stearates, stearamides and also esters ofpentaerythritol with long-chain fatty acids.

It is further possible to add inorganic pigments such as titania,ultramarine blue, iron oxide and carbon black and organic pigments suchas phthalocyanines, quinacridones, perylenes and also dyes such asnigrosine and anthraquinones as colorants.

Sodium phenylphosphinate, alumina, silica, nylon 22 and preferably talccan be used as nucleating agents, customarily in amounts of up to 1% byweight.

Examples of plasticizers are dioctyl phthalate, dibenzyl phthalate,butyl benzyl phthalate, hydrocarbon oils, N-(n-butyl)benzenesulfonamideand o- and p-tolylethylsulfonamide.

The longlines 1 can also comprise a plurality of polyamide monofils A)which are knotted together. This is a preferred embodiment especiallyfor use as continuous lines in fishing.

The cylindrical hollow body (stopper 2) secured on the polyamide monofilconsists essentially of a thermoplastic elastomer having a Shore Dhardness (in accordance with DIN 53 505) of at least 50, preferably atleast 60, in particular at least 70.

Preferred thermoplastic elastomers are thermoplastic polyurethanes(TPUs), preferably (polyether)polyurethanes. Very particular preferenceis given to TPUs based on polytetrahydrofuran (PTHF) having an averagemolecular weight (M_(n)) of from 200 to 3000, preferably from 1000 to2000, as polyetherol components of the TPU.

Suitable TPUs can be prepared for example by reacting

a) organic, preferably aromatic, diisocyanates,

b) polyhydroxy compounds having molecular weights from 500 to 8000, and

c) chain extenders having molecular weights from 60 to 400 in thepresence of optionally

d) catalysts,

e) auxiliaries and/or additives.

The usable starting materials (a) to (c), catalysts (d), auxiliaries andadditives (e) will now be more particularly described:

a) Suitable organic diisocyanates (a) include for example aliphatic,cycloaliphatic and preferably aromatic diisocyanates. Specific examplesinclude aliphatic diisocyanates such as hexamethylene diisocyanate,cycloaliphatic diisocyanates such as isophorone diisocyanate,1,4-cyclohexane diisocyanate, 1-methyl-2,4- and -2,6-cyclohexanediisocyanate and also the corresponding isomer mixtures, 4,4′-, 2,4′-and 2,2′-dicyclohexylmethane diisocyanate and also the correspondingisomer mixtures and preferably aromatic diisocyanates such as2,4-toluylene diisocyanate, mixtures of 2,4- and 2,6-toluylenediisocyanate, 4,4′-, 2,4′- and 2,2′-diphenylmethane diisocyanate.Mixtures of 2,4′- and 4,4′-diphenylmethane diisocyanate,urethane-modified liquid 4,4′- and/or 2,4′-diphenylmethanediisocyanates, 4,4′-diisocyanato-1,2-diphenylethane and 1,5-naphthylenediisocyanate. Preference is given to using hexamethylene diisocyanate,isophorone diisocyanate, 1,5-naphthylene diisocyanate, diphenylmethanediisocyanate isomer mixtures having a 4,4′-diphenylmethane diisocyanatecontent of greater than 96% by weight and in particular4,4′-diphenylmethane diisocyanate.

b) Suitable high molecular weight polyhydroxy compounds (b) havingmolecular weights from 500 to 8000 are preferably polyetherols andpolyesterols. However, it is also possible to use hydroxyl-containingpolymers, for example polyacetals, such as polyoxymethylenes andespecially water-insoluble formals, eg. polybutanediol formal andpolyhexanediol formal, and polycarbonates, especially those formed fromdiphenyl carbonate and 1,6-hexanediol by transesterification, having theabovementioned molecular weights. The polyhydroxy compounds have to havean at least predominantly linear structure, ie. difunctional within themeaning of the isocyanate reaction. The polyhydroxy compounds mentionedcan be used as individual components or in the form of mixtures.

Suitable polyetherols can be prepared by reacting one or more alkyleneoxides having from 2 to 4 carbon atoms in the alkylene moiety with aninitiator molecule containing two active hydrogen atoms. Suitablealkylene oxides include for example ethylene oxide, 1,2-propylene oxide,1,2- and 2,3-butylene oxide. Preference is given to using ethylene oxideand mixtures of 1,2-propylene oxide and ethylene oxide. The alkyleneoxides can be used individually, alternatingly in succession or as amixture. Examples of suitable initiator molecules include water, aminoalcohols, such as N-alkyldiethanolamines, for exampleN-methyldiethanolamine, and diols, such as ethylene glycol,1,3-propylene glycol, 1,4-butanediol and 1,6-hexanediol. If desired, itis also possible to use mixtures of initiator molecules. Suitablepolyetherols further include the hydroxyl-containing polymerizationproducts of tetrahydrofuran (polyoxytetramethylene glycols).

Preference is given to using polyetherols formed from 1,2-propyleneoxide and ethylene oxide in which more than 50%, preferably from 60 to80%, of the OH groups are primary hydroxyl groups and in which at leastsome of the ethylene oxide forms a terminal block, in particular, forexample, polyoxytetramethylene glycols.

Such polyetherols can be obtained by for example polymerizing theinitiator molecule first with the 1,2-propylene oxide and then with theethylene oxide or initially copolymerizing all the 1,2-propylene oxidein a mixture with some of the ethylene oxide and then polymerizing therest of the ethylene oxide or stepwise by first polymerizing part of theethylene oxide, then all the 1,2-propylene oxide and then the rest ofthe ethylene oxide with the initiator molecule.

The essentially linear polyetherols have molecular weights from 500 to8000, preferably from 600 to 6000, in particular from 800 to 3500. Theycan be used not only individually but also in the form of mixtures withone another.

Suitable polyesterols are preparable for example from dicarboxylic acidshaving from 2 to 12 carbon atoms, preferably from 4 to 8 carbon atoms,and polyhydric alcohols. Suitable dicarboxylic acids include for examplealiphatic dicarboxylic acids, such as succinic acid, glutaric acid,adipic acid, suberic acid, azelaic acid and sebacic acid, and aromaticdicarboxylic acids, such as phthalic acid, isophthalic acid andterephthalic acid. The dicarboxylic acids can be used individually or asmixtures, for example in the form of a succinic, glutaric and adipicacid mixture. Similarly, it is possible to use mixtures of aromatic andaliphatic dicarboxylic acids. For preparing the polyesterols it can beadvantageous, if desired, to use not the dicarboxylic acids but thecorresponding dicarboxylic acid derivatives, such as dicarboxylic estershaving from 1 to 4 carbon atoms in the alcohol moiety, dicarboxylicanhydrides or dicarbonyl chlorides. Examples of polyhydric alcohols areglycols having from 2 to 10, preferably from 2 to 6, carbon atoms, suchas ethylene glycol, diethylene glycol, 1,4-butanediol, 1,5-pentanediol,1,6-hexanediol, 1,10-decanediol, 2,2-dimethyl-1,3-propanediol,1,3-propanediol and dipropylene glycol. Depending on the propertiesdesired, the polyhydric alcohols can be used alone or if desired inmixtures with one another.

Also suitable are esters of carbonic acid with the diols mentioned, inparticular those having from 4 to 6 carbon atoms, such as 1,4-butanedioland/or 1,6-hexanediol, condensation products of w-hydroxycarboxylicacids, for example w-hydroxycaproic acid, and preferably polymerizationproducts of lactones, for example substituted or unsubstitutedw-caprolactones.

Preferred polyesterols are dialkylene glycol polyadipates having from 2to 6 carbon atoms in the alkylene moiety, eg. ethanediol polyadipates,1,4-butanediol polyadipates, ethanediol butanediol 1,4-polyadipates,1,6-hexanediol neopentyl-glycol polyadipates, polycaprolactones andespecially 1,6-hexanediol 1,4-butanediol polyadipates.

The polyesterols have molecular weights from 500 to 6000, preferablyfrom 800 to 3500.

c) Suitable chain extenders (c) having molecular weights from 60 to 400,preferably from 60 to 300, preferably include aliphatic diols havingfrom 2 to 12 carbon atoms, preferably having 2, 4 or 6 carbon atoms, eg.ethanediol, 1,6-hexanediol, diethylene glycol, dipropylene glycol andespecially 1,4-butanediol. However, it is also possible to use diestersof terephthalic acid with glycols having from 2 to 4 carbon atoms, forexample bisethylene glycol or bis-1,4-butanediol terephthalate,hydroxyalkylene ethers of hydroquinone, eg.1,4-di(β-hydroxyethyl)hydroquinone, (cyclo)aliphatic diamines, eg.4,4′-diaminodicyclohexylmethane,3,3′-dimethyl-4,4′-diaminodicyclohexylmethane, isophoronediamine,ethylenediamine, 1,2-, 1,3-propylenediamine,N-methylpropylene-1,3-diamine, N,N′-dimethylethylenediamine, andaromatic diamines, eg. 2,4- and 2,6-toluylenediamine, 3,5-diethyl-2,4-and -2,6-toluylenediamine and primary ortho-di-, -tri- and/or-tetra-alkyl-substituted 4,4′-diaminodiphenylmethanes.

To control TPU hardness and melting point, formative components (b) and(c) can be varied within relatively wide molar ratios. It isadvantageous to use molar ratios of polyhydroxy compounds (b) to chainextenders (c) of from 1:1 to 1:12, especially from 1:1.8 to 1:6.4, inwhich case the hardness and the melting point of the TPUs increase withincreasing diol content.

To prepare the TPUs, formative components (a), (b) and (c) are reactedin the presence of optionally catalysts (d), auxiliaries and/oradditives (e) in such amounts that the equivalence ratio of NCO groupsof diisocyanates (a) to the sum of the hydroxyl groups or hydroxyl andamino groups of components (b) and (c) is within the range from 1:0.85to 1:1.20, preferably from 1:0.95 to 1:1.05, especially from 1:0.98 to1:1.02.

d) Suitable catalysts which speed up in particular the reaction betweenthe NCO groups of diisocyanates (a) and the hydroxyl groups of formativecomponents (b) and (c) include the well known and customary tertiaryamines, eg. triethylamine, dimethylcyclohexylamine, N-methylmorpholine,N,N′-dimethylpiperazine, 2-(dimethylaminoethoxy)ethanol,diazabicyclo(2,2,2)octane and the like and in particular organic metalcompounds such as titanic esters, iron compounds such as iron(III)acetylacetonate, tin compounds, eg. tin diacetate, tin dioctoate, tindilaurate or the tin dialkyl salts of aliphatic carboxylic acids such asdibutyltin diacetate, dibutyltin dilaurate or the like. The catalystsare customarily used in amounts from 0.001 to 0.1 part per 100 parts ofpolyhydroxy compound (b).

As well as catalysts, formative components (a) to (c) may alsoincorporate auxiliaries and/or additives (e), in amounts of up to 40,preferably up to 20, % by weight, based on 100% of thermoplasticelastomer. Examples are lubricants, inhibitors, stabilizers againsthydrolysis, light, heat or discoloration, dyes, pigments, inorganicand/or organic fillers and plasticizers.

Details about the abovementioned auxiliary and additive substances aregiven in the technical literature, for example the monograph by J. H.Saunders and K. C. Frisch, “High Polymers”, Volume XVI, Polyurethanes,Parts 1 and 2, Verlag Interscience Publishers 1962 and 1964,respectively, or DE-B2901774.

The stoppers 2 of the longlines of this invention are particularlyadvantageously made with those TPUs which include up to 25, preferablyup to 15, % by weight of fibrous filler, preferably glass fibers.

Suitable products are commercially available as Elastollan® 1174D,Elastollan®R3000 and Elastollan®R3001, from ElastogranGmbH, DE.

For better flexural strength, stopper 2 can be provided with at leastone radial constriction. It preferably has at least 3 and in particular5 radial constrictions. Generally the external diameter is from 3 to 10mm, preferably from 6 to 8 mm. The length of the stopper on themonofilament is customarily from 10 to 80 mm, preferably from 20 to 30mm.

The spacing of the stoppers on the monofil is generally not critical anddepends essentially on the intended use. For example, two stoppers canfirmly grasp one clip 3 with associated hookline 5, in which case carehas to be taken to ensure that the distance to the two nearest stoppersplus clips and hookline is sufficient for the hooklines not to becomemutually entangled. In a further embodiment of the longlines, the clipsplus hooklines can be limited in their mobility along the line byindividual stoppers.

A conventional hookline is attached to clip 3 by a hook 4 and isattached at its other end to a fishhook 6.

The clip, which is freely rotatable about the longline, can also bemoved along the longitudinal direction (eg. by the fish) as a result. Ina further embodiment it is also possible to apply clips (plus hooklines)on the stoppers themselves. Such clips are freely rotatable about theline, but are not free to move in the longitudinal direction of theline.

We have also found a process for manufacturing a longline, whichcomprises

a) extruding a polyamide melt through a die to form a polyamide monofil,

b) cooling the monofil,

c) drawing the monofil in the longitudinal direction in at least onefurther step,

d) relaxing the monofil, and then

e) securing said stoppers b) on the monofil.

In general, the aforementioned polyamides are introduced as pellets withor without further, additive substances into suitable apparatus, forexample extruders, and processed to form a homogeneous melt which isextruded through a die so as to form a monofil.

The extruded monofils can be cooled in one or more stages by passingmonofils through one or more successive waterbaths.

The cooling water in these baths is customarily regulated and/orcirculated so that temperatures from 10 to 20° C., preferably from 15 to25° C., are achieved.

The monofils are then drawn in the longitudinal direction in at leastone further process step. Preferably, to improve the adhesion of thestopper, the monofil cross-section is flattened by suitable means (eg.an embossing station) before drawing, preferably at the position of thestopper on the longline and over the length which the stopper issubsequently intended to occupy on the line.

Process step c) in a preferred embodiment is carried out in at least 2stages, at least one drawing being carried out in steam at temperaturesfrom 95 to 105° C., preferably from 100 to 102° C., and at least onefurther drawing being carried out in hot air at temperatures from 240 to330° C., preferably from 270 to 310° C.

For this the monofils are for example passed over rolls which rotate atdifferent speeds so that the monofils are drawn to a draw ratio of notmore than 7, preferably not more than 6.3, in total.

In the preferred two-stage embodiment, the drawing in steam is to a drawratio of from 3.2 to 4.2 and the drawing in hot air is to a draw ratioof from 1.24 to 1.82, making a total draw ratio for the two stages offrom 5.2 to 5.8.

This preferred drawing leads in particular to an increase in the knotstrength of the monofils. Subsequently, the monofils are relaxed overrolls which rotate slower than the draw rolls by a factor of from 0.90to 0.98, preferably from 0.93 to 0.96.

Relaxation generally serves to stabilize and set the drawn monofilproperties and is generally carried out at temperatures from 140 to 220°C., preferably from 160 to 190° C.

The monofils then have stoppers B) applied to them by means of suitableprocesses, for example welding or injection-molding processes (see forexample NO-A 87/0531).

To improve the adhesion of the stopper on the monofil surface, thelatter can preferably be pretreated, in which case a pretreatment can becarried out in particular by means of the corona process.

The corona surface effect is due to the bombarding of the polymersurface with electrons. These leave the electrode and are accelerated bythe effect of the high voltage in the direction of the moving web. Onthe way they collide with air molecules, which in turn emit light and insome instances react to form ozone and nitrogen oxides. When theelectrons impact the polymer, they have so much energy that they canbreak the bonding, for example between carbon and hydrogen or betweentwo carbon atoms. The free valences (radicals) are then the site ofreactions with the corona gas, predominantly oxidations.

The functional groups formed are polar and hence the basis for theadhesion of, for example, applied printing inks, coatings, etc.

The best effectivity is achieved when the discharge is very uniform andthe discharge current is very high while sparks are gentle. Thedischarge current depends on generator power and on the electricalcoordination of generator, high voltage transformer, electrode andcounter-electrode. The gentle and homogeneous sparks profile isdetermined by the design and construction of the electrode and theworking frequency of the generator.

In a particularly preferred embodiment, the pretreatment can be effectedfor example by passing the monofil through a high voltage field, inwhich case the monofil surface is statically charged up in parts viamultipoint electrodes.

The longlines of this invention are useful for manufacturing anglinglines, fishlines and especially continuous lines for catching fish.Apparatus and processes for securing the clips plus hooklines arediscernible for example from EP-A 537 193, U.S. Pat. No. 4,407,087 andalso technical publications of Mustad & Søn, Norway.

EXAMPLES I. Monofil Production

Polyamide granules comprising a copolyarnide with 85% by weight of PA6and 15% by weight of PA66 units (Ultramid® C4 from BASF AG) with aviscosity number (VN) of 250 ml/g (measured on a 0.5% strength by weightsolution in 96% strength by weight H₂SO₄ at 25° C. in accordance withISO307) were melted in an extruder at 280° C., the melt was extruded at285° C., and the extrudate was cooled by a waterbath at 19° C. Thedrawing was carried out in a 1st stage in steam (100° C.) to a drawratio of 4.1 and then in hot air at 305° C. to a total draw ratio of5.4. Subsequent relaxation at 185° C. shrank the monofil back, so thatthe post-relaxation draw ratio was 5.1.

TABLE 1 Properties of monofil Diameter Average mm 2.465 Minimum mm 2.327Maximum mm 2.613 Test condition Käfer MFT 30; n = 20 Fineness tex Testcondition weighed length: 0.6 m Dry tests Strength UTS N 2379.14 CV(coefficient of % 5.10 variation) UTS elongation % 31.8 CV % 11.30UTS/fineness cN/tex Test condition Zwick 1435; n = 10 (number ofmeasurements) Knot strength Average N 1710.63 Minimum N 1347.84 MaximumN 1889.28 CV % 8.62 Test condition Zwick 1435; L = 50 mm; n = 30Stiffness cN 72.0 Bending stress N/mm² 24.0 Test condition L. + W.; 30°bending radius; L = 50 mm; n = 10

II. Stopper

The following compositions were used:

1. For Comparison

polyamide 66 with VN 150 ml/g including 20% by weight of anethylene/acrylic acid/n-butyl acrylate/maleic anhydride copolymer(60/4.3/35/0.7) as toughener (Ultramid® A3Z from BASF AG)

2. For Comparison

polyamide 66 with VN 150 ml/g including 1% by weight of carbon black, 8%by weight of the same toughener as under 1. and 40% by weight of glassfibers (Ultramid®A3ZG8 from BASF AG)

3. For Comparison

polyamide 6 with VN 140 ml/g including 30% by weight of glass fibers(Ultramid®BEG6 from BASF AG)

4. A Thermoplastic Polyurethane (TPU) Formed from

polytetrahydrofuran (M_(n): 1000) (polyetherol),

4,4′-diphenylmethane diisocyanate (MDI),

1,4-butanediol

(Elastollan® 1174 D from Elastogran GmbH)

Shore D hardness (as defined in DIN 53505): 50

5. TPU Formed from

hexanediol butanediol adipate,

MDI,

1,4-butanediol

with 0.3% by weight of Stabaxol® (stabilizer based on an aromaticcarbodiimide)

and

20% by weight of glass fibers (Elastollan® R3000 from Elastogran GmbH)

Shore D hardness: 73

6. TPU Comprising

65% by weight of TPU formed from

a) butanediol adipate,

polytetrahydrofuran (M_(n): 1000),

polytetrahydrofuran (M_(n): 2000),

MDI,

butanediol

mixed with

19% by weight of TPU formed from

b) polytetrahydrofuran (M_(n): 1000),

MDI,

butanediol

stabilized with 0.2% by weight of Irganox® 1010 (Ciba Geigy AG)

1% by weight of carbon black

15% by weight of glass fibers

(Elastollan® R 3001 from ElastogranGmbH)

Shore D hardness: 75

III. Production of Longlines

Stoppers 1 to 6 were applied to the monofil by injection molding. Themelt temperatures are shown in the table.

The number of radial constrictions was: 5

Length of stopper: 30 mm

Diameter (outer) of stopper: 7 mm

IV. Pretreatment of Monofils

Type 1: Corona Pretreatment by Softal, Hamburg

corona pretreatment via two ceramic electrodes having dimensions

12×16×100 mm

applied voltage: 10 kV

monofil-electrode distance 0.6 mm

pulloff speed: 1 m/min

Type 2:Pretreatment on Carrier Roll (Corona Apparatus for Films fromSoftal, Hamburg)

knife electrode with 11 steel knives

roll diameter: 255 mm

applied voltage: 1 kV

Knife electrode-monofil distance: 2 mm

roll circumferential speed: 40 m/min

number of roll revolutions: 2×3 (monofils treated from both sides)

Type 3: Pretreatment via KNH 34 High Voltage Generator from Eltex, Weilam Rhein

Principle: Partial Chargeup of Monofil Surface via Three Point Electrode

applied voltage via generator: 20 kV

electrode-monofil distance: 50-70 mm

treatment time 2×3 s (monofil treated from both sides)

The pulloff resistance of the stopper [N] was measured in accordancewith the data given below in the table

a) following air aging at room temperature

b) following water aging (24 h) at room temperature and

c) with or without pretreatment of the monofil.

The pulloff resistance was measured on a Zwick 1435 tensile tester byfixing the longline in a clamp. The stopper was guided above the rollthrough a metal bolt having a round throughole so that the stopper cameto rest on the bolt. The bolt is then guided upward while the forcerequired to detach the stopper from the monofil is measured.

The results of the measurements are shown in table 2.

TABLE 2 Melt Average Exam- Stopper temperature Aging Pre- pulloff forceple type [° C.] Air Water treatments [N]   1C 1 280 + − — 224   2C 2280 + − — 520   3C 2 295 + − — 559   4C 2 300 + − — 590   5C 3 280 + − —449  6 4 230 + − — 764  7 4 230 − + — 834  8 4 230 − + Type 2 925  9 4230 + − Type 3 874 10 4 230 − + Type 3 1040 11 5 250 + − — 1011 12 5 250− + — 1004 13 5 250 − + Type 1 968 14 5 250 − + Type 2 995 15 5 250 + −Type 3 1073 16 5 250 − + Type 3 943 17 6 250 + − — 1222 18 6 250 − + —1250 19 6 250 − + Type 2 1180 20 6 250 + − Type 3 1327 21 6 250 − + Type3 1220

We claim:
 1. A longline comprising at least one polyamide monofil withat least one stopper secured on the polyamide monofil surface, whereinsaid stopper consists essentially of a thermoplastic elastomer having aShore D hardness of at least
 50. 2. A longline as defined in claim 1,wherein the outer surface of said stopper is provided with at least oneradial constriction.
 3. A longline as defined in claim 1, wherein saidthermoplastic elastomer has a Shore D hardness of at least
 70. 4. Alongline as defined in claim 1, wherein said thermoplastic elastomerincludes up to 40% by weight of further additive substances andprocessing aids.
 5. A longline as defined in claim 1, wherein saidthermoplastic elastomer consists essentially of a thermoplasticpolyurethane.
 6. A longline as defined in claim 1, wherein the polyamideof said monofil has a viscosity number of at least 180 ml/g.
 7. Alongline as defined in claim 1, wherein the polyamide of said monofilcomprises PA6 or 6/66 copolyamide or mixtures thereof.
 8. Angling lines,fishlines and continuous lines for catching fish, formed from thelonglines of claim
 1. 9. A process for manufacturing a longline, whichlongline comprises at least one polyamide monofil with at least onestopper secured on the polyamide monofil surface, wherein said stopperconsists essentially of a thermoplastic elastomer having a Shore Dhardness of at least 50, which process comprises a) extruding apolyamide melt through a die to form a polyamide monofil, b) cooling themonofil, c) drawing the monofil in the longitudinal direction in atleast one further step, d) relaxing the monofil, and then e) securingsaid at least one stopper on the monofil.
 10. A process as defined inclaim 9, wherein the monofil cross-section is flattened before thedrawing (step c).
 11. A process as defined in claim 9, wherein step c)is carried out in at least 2 stages, at least one drawing being carriedout in steam and at least one further drawing in hot air.
 12. A processas defined in claim 9, wherein the monofil is drawn to a draw ratio ofnot more than 7 in total.
 13. A process as defined in claim 9, whereinthe monofil surface is pretreated before the securing of said stoppersB).
 14. A process as defined in claim 9, wherein the monofil surface ispretreated by means of the corona process or by means of high voltage.